The risk of Brettanomyces contamination during the winemaking process is an economic threat for producers. Indeed, these yeasts develop easily in wine, producing volatile phenols, responsible for undesirable aromas. The detection of active yeasts is a crucial issue since it can allow early treatment to be implemented in the event of contamination.

Amarok Biotechnologies studied the effectiveness of a detection method under development. It uses an original method based on magnetic beads coupled with antibodies.

How does the new method of identifying Brett using magnetic beads work?

The 0.1 µm electromagnetic beads are coupled to specific antibodies which bind to the Bretts and allow their capture. A magnetic separation is then carried out. After marking the active yeasts with the FDA (fluorescein diacetate), the detection is done by flow cytometry.

An effective and specific analysis method for active Brettanomyces

The beads specifically capture Brett, and fluorescent labeling allows quantification of only viable cells that threaten wine quality.

Good prospects for developments in the test

We anticipate several developments:

• screening of Brett strains and other genera to confirm specificity;
• adaptation of the method to a wine matrix;
• carrying out a complete validation (linearity, precision, stability of the reagents).

Our laboratory is also planning the use of different antibodies to adapt the method to contaminants other than Brettanomyces.